Patents Assigned to Numar Corporation
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Patent number: 6583621Abstract: A method for manufacturing NMR measurement-while-drilling tool having the mechanical strength and measurement sensitivity to perform NMR measurements of an earth formation while drilling a borehole, and a method and apparatus for monitoring the motion of the measuring tool in order to take this motion into account when processing NMR signals from the borehole. The tool has a permanent magnet with a magnetic field direction substantially perpendicular to the axis of the borehole, a steel collar of a non-magnetic material surrounding the magnet, antenna positioned outside the collar, and a soft magnetic material positioned in a predetermined relationship with the collar and the magnet that helps to shape the magnetic field of the tool. Due to the non-magnetic collar, the tool can withstand the extreme conditions in the borehole environment while the borehole is being drilled.Type: GrantFiled: March 27, 2002Date of Patent: June 24, 2003Assignee: Numar CorporationInventors: Manfred G. Prammer, James H. Dudley, Peter Masak, George D. Goodman, Marian Morys, Dale A. Jones, Roger P. Bartel, Chen-Kang David Chen, Michael L. Larronde, Paul F. Rodney, John E. Smaardyk
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Publication number: 20020163335Abstract: A method for manufacturing NMR measurement-while-drilling tool having the mechanical strength and measurement sensitivity to perform NMR measurements of an earth formation while drilling a borehole, and a method and apparatus for monitoring the motion of the measuring tool in order to take this motion into account when processing NMR signals from the borehole. The tool has a permanent magnet with a magnetic field direction substantially perpendicular to the axis of the borehole, a steel collar of a non-magnetic material surrounding the magnet, antenna positioned outside the collar, and a soft magnetic material positioned in a predetermined relationship with the collar and the magnet that helps to shape the magnetic field of the tool. Due to the non-magnetic collar, the tool can withstand the extreme conditions in the borehole environment while the borehole is being drilled.Type: ApplicationFiled: March 27, 2002Publication date: November 7, 2002Applicant: Numar CorporationInventors: Manfred G. Prammer, James H. Dudley, Peter Masak, George D. Goodman, Marian Morys, Dale A. Jones, Roger P. Bartel, Chen-Kang David Chen, Michael L. Larronde, Paul F. Rodney, John E. Smaardyk
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Patent number: 6377042Abstract: Proposed is a new method and system to obtain enhanced-resolution NMR data by merging, in the time domain, different NMR pulse echo trains into a single echo train. The input echo trains can be acquired with different inter-echo spacing, wait time, and signal-to-noise ratio parameters that are optimized to correspond to both fast and slow portions of the T2 spectrum. The merged echo trains are inverted into complete T2 spectra in a single step thereby overcoming ambiguities and other limitations of prior art methods. In a preferred embodiment the merging process does not require a priori information about T1, and the merged echo trains are optimized in with respect to T2 resolution. The method of this invention is preferably practiced with the latest generation of multi-volume NMR logging tools, that allow simultaneous recordation of NMR data with different inter-echo spacing Te, wait time Tw, and signal-to-noise ratio (SNR) parameters.Type: GrantFiled: August 10, 1999Date of Patent: April 23, 2002Assignee: NUMAR CorporationInventors: Stefan K. Menger, Manfred G. Prammer
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Patent number: 6362619Abstract: An NMR measurement-while-drilling tool having the mechanical strength and measurement sensitivity to perform NMR measurements of an earth formation while drilling a borehole, and a method and apparatus for monitoring the motion of the measuring tool in order to take this motion into account when processing NMR signals from the borehole. The tool has a permanent magnet with a magnetic field direction substantially perpendicular to the axis of the borehole, a steel collar of a non-magnetic material surrounding the magnet, antenna positioned outside the collar, and a soft magnetic material positioned in a predetermined relationship with the collar and the magnet that helps to shape the magnetic field of the tool. Due to the non-magnetic collar, the tool can withstand the extreme conditions in the borehole environment while the borehole is being drilled.Type: GrantFiled: July 31, 2001Date of Patent: March 26, 2002Assignee: Numar CorporationInventors: Manfred G. Prammer, James H. Dudley, Peter Masak, George D. Goodman, Marian Morys, Dale A. Jones, Roger P. Bartel, Chen-Kang David Chen, Michael L. Larronde, Paul F. Rodney, John E. Smaardyk
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Patent number: 6316940Abstract: A novel method and system is disclosed for the separation of fluid phases in NMR borehole measurements. The method is based on forcing diffusion as the dominant relaxation mechanism for certain fluid phase by adjusting certain user controlled parameters. The invention is more specifically applicable to separation of brine from hydrocarbons, using enhanced diffusion to establish an upper limit for the T2 spectral distribution of the brine. Parameters that can be modified to enhance the diffusion relaxation during the measurements include the interecho spacing TE and the magnetic field gradient G of the measurement tool.Type: GrantFiled: March 17, 1999Date of Patent: November 13, 2001Assignee: Numar CorporationInventor: Ridvan Akkurt
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Patent number: 6268726Abstract: An NMR measurement-while-drilling tool having the mechanical strength and measurement sensitivity to perform NMR measurements of an earth formation while drilling a borehole, and a method and apparatus for monitoring the motion of the measuring tool in order to take this motion into account when processing NMR signals from the borehole. The tool has a permanent magnet with a magnetic field direction substantially perpendicular to the axis of the borehole, a steel collar of a non-magnetic material surrounding the magnet, antenna positioned outside the collar, and a soft magnetic material positioned in a predetermined relationship with the collar and the magnet that helps to shape the magnetic field of the tool. Due to the non-magnetic collar, the tool can withstand the extreme conditions in the borehole environment while the borehole is being drilled.Type: GrantFiled: January 15, 1999Date of Patent: July 31, 2001Assignee: Numar CorporationInventors: Manfred G. Prammer, James H. Dudley, Peter Masak, George D. Goodman, Marian Morys, Dale A. Jones, Roger P. Bartel, Chen-Kang David Chen, Michael L. Larronde, Paul F. Rodney, John E. Smaardyk
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Patent number: 6242912Abstract: A well logging system and method are disclosed for detecting the presence and estimating the quantity of gaseous and liquid hydrocarbons in the near wellbore zone. The system uses a gradient-based, multiple-frequency NMR logging tool to extract signal components characteristic for each type of hydrocarbons. To this end, a new data acquisition method is proposed in which measurements at different frequencies are interleaved to obtain, in a single logging pass, multiple data streams corresponding to different recovery times and/or diffusivity for the same spot in the formation. The resultant data streams are processed to determine mineralogy-independent water and hydrocarbon saturations and porosity estimates. Gas and oil saturations are used to obtain accurate estimates of the water content, permeability and other parameters of interest.Type: GrantFiled: March 19, 1997Date of Patent: June 5, 2001Assignee: Numar CorporationInventors: Manfred G. Prammer, Duncan Mardon, George R. Coates, Melvin N. Miller
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Patent number: 6242913Abstract: A logging while drilling (LWD) and measuring while drilling (MWD) method and device are disclosed for reducing the sensitivity of NMR measurements to tool motions. The invention is based on NMR relaxation measurements determining longitudinal relaxation times T1 instead of the standard T2 measurements, and involves saturating a relatively wide sensitive region of the formation and processing NMR echo signals which originate approximately from the center of the sensitive region.Type: GrantFiled: April 18, 2000Date of Patent: June 5, 2001Assignee: Numar CorporationInventor: Manfred Prammer
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Patent number: 6204663Abstract: Novel pulse sequence and data acquisition method are disclosed which eliminate the effects of spurious NMR signals caused by mechanical resonances within the measurement apparatus. The proposed method alleviates interference problems typically arising from strong “excitation” pulses in a sequence, and enables the use of the corresponding data points to increase the resolution of the measurement. The method is based on changing the measurement frequency between pulse sequences and averaging out data points obtained from the different sequences in a way that effectuates cancellation of the spurious signals. The novel cycle of ulse sequences and a data acquisition method can be used, or example, with any existing NMR logging instruments.Type: GrantFiled: March 26, 1997Date of Patent: March 20, 2001Assignee: Numar CorporationInventor: Manfred G Prammer
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Patent number: 6111408Abstract: A method and apparatus are disclosed for using nuclear magnetic resonance (NMR) techniques to obtain information relating to fluids present near geologic structures. A modular NMR tester which can be located within a standard modular logging tool is used for direct downhole NMR measurements of various parameters of fluid samples of geologic formations near the walls of a borehole. The tester has a vessel made of a non-conductive material and a surrounding permanent magnet that creates a uniform static magnetic field within the test chamber of the vessel. An RF coil is embedded in the walls of the vessel and is used to induce excitation field with a direction perpendicular to the static magnetic field. Fluids located proximate the borehole are introduced into a test chamber of the tester. NMR signals from the excited nuclei in the fluids are detected to obtain data for calculating a number of important fluid parameters and for the interpretation of wireline MRIL measurements.Type: GrantFiled: December 23, 1997Date of Patent: August 29, 2000Assignee: Numar CorporationInventors: Thomas Blades, Manfred Prammer
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Patent number: 6107796Abstract: A method and apparatus for processing nuclear magnetic resonance (NMR) information to differentiate between oil based mud filtrate (OBM), and connate oils, during subsurface exploration. An NMR experiment is performed on a sample of formation fluid, and the resulting data is then processed to differentiate between the relaxation time parameters characteristic of OBMs and those characteristic of connate oils. A simple arithmetic difference between relaxation times calculated for successive samples may be followed by a distributional analysis performed in either the time domain or relaxation spectrum domain. The process is repeated for other fluid samples and the data for successive fluid samples is compared so that the user may determine when the formation fluid consists almost entirely of connate oil.Type: GrantFiled: August 17, 1998Date of Patent: August 22, 2000Assignee: Numar CorporationInventor: Manfred G. Prammer
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Patent number: 6051973Abstract: A logging while drilling (LWD) and measuring while drilling (MWD) method and device are disclosed for reducing the sensitivity of NMR measurements to tool motions. The invention is based on NMR relaxation measurements determining longitudinal relaxation times T1 instead of the standard T2 measurements, and involves saturating a relatively wide sensitive region of the formation and processing NMR echo signals which originate approximately from the center of the sensitive region.Type: GrantFiled: December 23, 1997Date of Patent: April 18, 2000Assignee: Numar CorporationInventor: Manfred Prammer
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Patent number: 6023164Abstract: A method and apparatus are described using nuclear magnetic resonance (NMR) measurements for obtaining information relating to properties of geologic structures in highly conductive borehole environments. A centralized NMR logging probe is provided with a sleeve having a semi-circular RF shield that blocks signals from one side of the probe and with elements that press the uncovered side of the probe to the sidewall of the borehole. In highly conductive boreholes, the eccentrically-positioned modified probe results in increased signal-to-noise ratios and savings in peak power and energy compared with the use of standard centralized tools. The modified probe further suppresses unwanted NMR signals.Type: GrantFiled: February 20, 1998Date of Patent: February 8, 2000Assignee: Numar CorporationInventor: Manfred Prammer
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Patent number: 6005389Abstract: An NMR pulse sequence and signal processing method is disclosed for measurement of fast decay response signals from materials containing a fluid state. The proposed pulse sequence and processing method are applicable in borehole NMR logging as well as measurements of attributes of man-made or natural materials. The disclosed pulse sequence comprises a series of short NMR pulse trains separated by intervals which are shorter than the time required for polarization of nuclear magnetization in bulk fluids of the fluid state. By stacking response signals to increase the signal to noise ratio, time domain data is obtained that generally corresponds to transverse decay components as short as about 0.5 ms. Various attributes of the materials being investigated can be derived in a single measurement.Type: GrantFiled: March 13, 1997Date of Patent: December 21, 1999Assignee: Numar CorporationInventor: Manfred G. Prammer
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Patent number: 5936405Abstract: A well logging system and method for detecting the presence and estimating the quantity of gaseous and liquid hydrocarbons in the near wellbore zone. The system uses a gradient-based, multiple-frequency NMR logging tool to extract signal components characteristic for each type of hydrocarbons. To this end, a new data acquisition method is proposed in which measurements at different frequencies are interleaved to obtain, in a single logging pass, multiple data streams corresponding to different recovery times and/or diffusivity for the same spot in the formation. The resultant data streams are processed to determine mineralogy-independent water and hydrocarbon saturations and porosity estimates. Gas and oil saturations are used to obtain accurate estimates of the water content, permeability and other parameters of interest.Type: GrantFiled: September 25, 1996Date of Patent: August 10, 1999Assignee: Numar CorporationInventors: Manfred G Prammer, Duncan Mardon, George R Coates, Melvin N Miller
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Patent number: 5696448Abstract: A simple, pore-level model for diffusion and NMR relaxation of oil-water mixtures in water wet pores has been developed. In addition to lending physical insight into the relaxation time behavior of mixed pore fluids, the model can be used to generate a practical tool for interpreting diffusion log data, i.e., a T2 vs. D cross plot. Locating points on the cross plot simultaneously yields the near wellbore water saturation and the rock pore size. For light oils, T2 is shown to be mainly a pore size indicator whereas D is controlled mainly by Sw. The pore size "resolution" decreases as oil viscosity and/or Sw decreases. A preliminary verification of the model has been made with limited core data and the results of applying the model to interpreting NMR log data are encouraging.Type: GrantFiled: June 26, 1995Date of Patent: December 9, 1997Assignee: Numar CorporationInventors: George R. Coates, Duncan Mardon, Daniel L. Miller
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Patent number: 5557200Abstract: An improved system for using magnetic resonance techniques to obtain information relating to geologic structures is disclosed. The system of the present invention uses values of the total porosity of a formation and the porosity obtained via NMR pulse echo techniques to derive additional information relating to the underlying geologic structures, including resistivity and water saturation. Independent estimate is provided to account for the presence of clay mineral content.Type: GrantFiled: June 17, 1994Date of Patent: September 17, 1996Assignee: Numar CorporationInventor: George R. Coates
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Patent number: 5517115Abstract: A method and apparatus is disclosed for efficient processing of nuclear magnetic resonance (NMR) echo trains in well logging. Apriori information about the nature of the expected signals is used to obtain an approximation of the signal using a set of pre-selected basis functions. A singular value decomposition (SVD) is applied to a matrix incorporating information about the basis functions, and is stored off-line in a memory. During the actual measurement, the apparatus estimates a parameter related to the SNR of the received NMR echo trains and uses it to determine a signal approximation model in conjunction with the SVD of the basis function matrix. This approximation is used to determine in real time attributes of the earth formation being investigated.Type: GrantFiled: December 16, 1993Date of Patent: May 14, 1996Assignee: Numar CorporationInventor: Manfred G. Prammer
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Patent number: 5412320Abstract: An improved system for using magnetic resonance techniques to obtain information relating to geologic structures. The system of the present invention uses values of bulk-volume irreducible water and porosity obtained via the magnetic resonance techniques to obtain additional information relating to geologic structures, including water saturation.Type: GrantFiled: June 15, 1992Date of Patent: May 2, 1995Assignee: Numar CorporationInventor: George R. Coates
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Patent number: 5309098Abstract: An improved system for using nuclear magnetic resonance techniques to obtain information relating to geologic structures. The system of the present invention employs a variable sampling window which increases sampling efficiency by allowing the system to optimize the sampling interval, thereby maximizing the amount of data which can be obtained in a series of data samples.Type: GrantFiled: November 27, 1991Date of Patent: May 3, 1994Assignee: Numar CorporationInventors: George R. Coates, Melvin N. Miller, John C. Bouton